Hi. I need to build a mini treadmill for my project and I had a few questions which I hope you guys could answer. The treadmill needs to run at a maximum speed of 0.4 km/hr for around 3-4 hours. I also need to be able to control the speed somehow? The weight of the object on the treadmill is going to be less than a pound (It is a lizard treadmill). I was thinking about using an AC motor, but those are expensive with a pot to control the speed? What would you guys suggest is the best motor type I should use? AC or DC motor? Also, how would I control the speed? Would a pot be the best way to go or am I going to need to create a PWM signal with an arduino or something similar?